How do you get your decks so effing modified during a run?

I see some of you with entire decks or nearly entire decks of like steel Kings with red seals and god-tier Jokers that synergize with those.

I understand that outside of using seeds the Jokers are pure RNG. I don't know, however, how anyone has time in a match to get every card in their deck modified, or nearly every card.

I never seem to get enough Tarot or Spectral cards in a run to make any huge, consistent, meaningful modifications. When I can finally make, for example, a steel King with red seal, I will then never get a card to replicate it nor a card to remove other things. RNG doesn't give with both hands, it seems.

I usually make it a few antes past Ante 8 at my best, even using a runaway Plasma deck build. I have a feeling that the key to lots of modified cards is to keep the game going past Ante 8. How do you do both, though? Keep your game going long enough while building up lots of modified cards?